The short answer
Review concentrated bitter orange before using it with terbutaline, especially if you have palpitations or high blood pressure.
What this answer covers
Citrus aurantium extracts; food amounts, p-synephrine and synthetic stimulant adulterants are distinguished.
- Supplement or preparation
- Citrus aurantium
- Medication ingredient
- terbutaline
Why the medicine matters
Terbutaline can affect heart rate and blood pressure and its label cautions about other sympathomimetic medicines. A concentrated botanical stimulant warrants review, but the label does not measure this herbal pair.
Human findings differ
One bitter orange extract increased blood pressure and heart rate in a small study. Another p-synephrine study found no heart-rate increase and no added systolic effect with caffeine. The preparations and conditions differed, and neither included terbutaline.
Bring the full ingredient list
Bitter orange supplements can contain other stimulants or inaccurately labeled amines. Food use should not be treated as the same exposure as concentrated weight-loss products.
Keep the route and dose clear
The reviewed US products are sulfate tablets and subcutaneous injection. Human inhalation and intravenous studies are identified separately. Do not change the medicine dose or substitute a stimulant supplement for asthma treatment.
Respond to new symptoms
Report troublesome tremor, palpitations or weakness after a product change. Chest pain, fainting, a sustained irregular heartbeat or severe breathing difficulty needs urgent assessment. More frequent terbutaline use can indicate worsening asthma and needs a treatment review.
Evidence and practical considerations
Side effects & toxicity
Conditional cardiovascular concern has a preparation-specific basis, but increased exact-pair stimulant toxicity is not clinically demonstrated. Human bitter orange findings are mixed.
- Exact scope
- Citrus aurantium extracts; food amounts, p-synephrine and synthetic stimulant adulterants are distinguished. with Exact terbutaline sulfate oral tablets and subcutaneous injection. Exact RxNorm IN10368, sulfate oral tablet and subcutaneous injection. Intravenous and inhaled research exposures are explicitly separated from these labeled routes.
- Medication form and route
- oral; subcutaneous
- Timing or duration
- Source-specific single-dose, repeated-dose and observational exposures distinguished.
What remains uncertain
- No direct terbutaline-bitter orange study, no valid event rate or universal dose/interval.
Factors that may matter: preparation and plant part; clinical indication; dose; other medicines; baseline alertness.
Read the supporting source summaries
Source 1: current product label
dailymed.nlm.nih.gov · Source check Sep 10, 2026
Population: People prescribed terbutaline.
Cardiovascular and CNS stimulation, transient hypokalemia and other sympathomimetic precautions; animal methylxanthine combination findings have unknown clinical significance.
How this applies: Exact RxNorm IN10368, sulfate oral tablet and subcutaneous injection. Intravenous and inhaled research exposures are explicitly separated from these labeled routes.
No universal supplement dose, interval, event rate or untested formulation equivalence.
Source 2: current product label
dailymed.nlm.nih.gov · Source check Sep 10, 2026
Population: People prescribed terbutaline.
Cardiovascular and CNS stimulation, transient hypokalemia and other sympathomimetic precautions; animal methylxanthine combination findings have unknown clinical significance.
How this applies: Exact RxNorm IN10368, sulfate oral tablet and subcutaneous injection. Intravenous and inhaled research exposures are explicitly separated from these labeled routes.
No universal supplement dose, interval, event rate or untested formulation equivalence.
Source 3: original human study
pubmed.ncbi.nlm.nih.gov · Source check Sep 10, 2026
Population: Fifteen healthy adults in placebo-controlled crossover.
Blood pressure and heart rate were higher than placebo at some measured hours.
How this applies: Only the named drug, preparation, route and measured endpoints apply.
Single extract and healthy volunteers; no levalbuterol or terbutaline co-use, no clinical event rate.
Source 4: original human study
pubmed.ncbi.nlm.nih.gov · Source check Sep 10, 2026
Population: Sixteen subjects, double-blind comparison at rest.
No heart-rate difference; p-synephrine did not augment caffeine effects on systolic pressure; higher caffeine arms increased systolic pressure.
How this applies: Only the named drug, preparation, route and measured endpoints apply.
Short study at rest with specific preparations; no respiratory drug co-use and no general safety guarantee.
Source 5: official supplement guidance
nccih.nih.gov · Source check Sep 10, 2026
Population: People considering the specified supplement.
Cardiovascular findings are inconsistent; serious events often involve mixtures, and supplement composition can be inaccurate.
How this applies: Supplement-only context; explicit medication and preparation bridge required.
No exact respiratory medication interaction or equivalence to synthetic methylsynephrine.
Research assessment: · Open full citations ↗
Review and change history
- Publication status
- Published research summary
- Clinical review
- Not yet recorded
| Date | Update |
|---|---|
| Research summary published | |
| Article prepared | |
| Current exact available claims adjudicated using original captures and explicit identity and comparator limits. |
Article revision: 03a3a7d594115914
This guide brings together the evidence records used by our interaction checker. Each finding retains its own preparation limits, research date, and source summaries.
Full citations require verification. Reading this answer and the source summaries does not.
Taking other supplements or medications?
Use the checker to explore your other combinations. Ask a pharmacist to review the exact products, amounts and medical conditions in your complete list.
Open the interaction checkerInformation, not medical advice. Do not change prescribed treatment based on this guide.